Device for rotating the pattern cylinder of double-lift dobbies independently of itsnormal drive



Oct. 29, 1968 J. FUMAT 3,407,848

DEVICE FOR ROTATING THE PATTERN CYLINDER OF DOUBLELIFT DOBBIES INDEPENDENTLY OF ITS NORMAL DRIVE Filed Jan. 25, 1967 INVENT OR ATTORNEK United States Patent Claims. 'icl. 139-1 ABSTRACT OF THE DISCLOSURE Adevice for driving a dobby pattern cylinder independently of its drive means having control means operative to disengage the normal cylinder drive means and the pattern reading means and through motor means drive the cylinder a predetermined distance in either direction to properly position the pattern after a looin stoppage.

The present invention relates to do bbies for looms and it more particularly concerns double-lift dobbies wherein selection is effected by means of feeler needles and of a perforated paper band, each card of which (i.e., each one of the successive zones of the band on which the feeler needles are lowered) corresponds to two successive picks of the loom, the heald shafts being actuated by two sets of hooks.

The disadvantage of these double-lift dobbies is that it is difficult to set correctly the pattern with respect to the fabric being woven when for any reason, as for instance owing to a defect in the fabric, the loom has to be stopped and a number of wefts have to be unwoven. The operator must operate the dobby backwards through one card before beginning the unweaving operation and then backwards through the same amount for each two successive picks while disengaging the filling threads until the defect has been removed. It is thereafter necessary to advance the cylinder of the dobby through one card in order to obtain correct operation when the loom is re-started.

-It has been proposed to avoid this drawback by providing two feeler needles for each hook of the dobby, all these needles being disposed in four rows. With such an arrangement and if the paper band is appropriately perforated, the loom may be directly re-started without any previous advance of the cylinder of the dobby. But this particular construction of the dobby is rather intricate and therefore expensive.

It is an object of the present invention to avoid these disadvantages by providing a device which, under the effect of the manual actuation of a single lever, will automatically cause the dobby to be driven either forwardly or rearwardly while effecting automatically the preliminary displacement of the perforated paper band through an amount corresponding to one card, as required for a correct operation.

The device according to the present invention essentially comprises a single lever which, when it is actuated in a first direction starting from its position of rest, momentarily raises the feeler needles, momentarily disengages the positioning pawl of the paper carrying cylinder, rotates the latter backwards through an angle corresponding to one card, i.e., to two picks of the loom, then liberates 3,407,848 Patented Oct. 29, 1968 Preferably when the said lever is actuated in the reverse or second direction starting from its position of rest, it only de-clutches the dobby from the loom in order to permit free rotation of the dobby in the forward direction.

According to another aspect of the present invention, at the end of its stroke in the first or in the second direction the lever further actuates a switch which energizes an auxiliaiy motor adapted to drive the dobby respectively forwardly or backwardly. In a preferred embodiment the lever first clutches the auxiliary motor with the dobby and thereafter actuates a reversing switch which energizes the motor for rotation in the proper direction.

In the accompanying drawings:

FIG. 1 is a fragmental perspective view diagrammatically illustrating the main components of a device according to the present invention together with those of the double-lift dobby with which this device cooperates.

FIG. 2 is an enlarged side view of the main portion of the device.

FIG. 3 is a general diagrammatical view illustrating some parts omitted in FIGS. 1 and 2.

The annexed drawings only show the parts of the double-lift dobby which are necessary for a clear understanding of the present invention. It should be noted in this respect that this dobby is in itself of quite conventional construction. It comprises two sets of reciprocating hooks which are appropriately selected under the action of feeler needles and of a perforated paper pattern which is programmed as successive pattern cards. This band is shown at 1 in FIG. 1. It is supported by a cylinder 2 formed of pegged wheels the teeth or pegs 3 of which engage rows of perforations provided along the edges of the band. These pegged wheels are carried by a shaft 4 on which is keyed an advancing wheel 5 intermittently actuated by a finger (not illustrated) carried by a continuously rotating arm. Between its successive periods of advance this wheel 5 is retained in position by a positioning pawl formed of a gudgeon 6 supported by a lever 7 submitted to the action of a spring not shown, this gudgeon being momentarily disengaged fromthe wheel (i.e., raised in FIG. 3) by an appropriate cam gearing (not illustrated) during actuation of the wheel. The lever 7 is itself carried by a shaft 8 on which is mounted a pair of arms 9 connected with each other by a cross bar 10 adapted to raise and to lower a number of fingers 11, only one of which is shown, to which are individually attached the feeler needles 12. Each finger 11 is radially secured to a ring 13 loosely supported by the abovementioned shaft 8, this ring carrying a second finger 14 which is appropriately connected with a pusher needle (not shown) corresponding to one of the hooks of the dobby. In the conventional arrangement when a feeler needle 12 is retained by the paper band, the corresponding pusher needle is engaged by the corresponding bar and the hook with which the pusher rod is associated is raised.

The fingers 11 and the feeler needles 12 are cyclically raised together with the positioning pawl or igudgeon 6 by the cross-bar 10 during the advancing step of the perforated paper band 1, i.e., while the advancing finger (not shown) co-acts with the advancing wheel 5. When the paper band has been advanced, the feeler needles are again lowered, to read the card and effect selection of the dobby hooks. The feeler needles are disposed in two rows which respectively correspond to the upper hooks and to the lower hooks of the dobby which are thus selected simultaneously. Since these two sets of books operate alternatively, the selection is effected for two successive picks of the loom and each card of the paper band thus corresponds to two picks. The operating speed of the selecting gearing of the dobby is therefore one half the speed of'the loom, which is of course a marked advantage.

But as aforesaid the dobbies of the kind in question afford the inconvenience that when the operator has to proceed to an unweaving operation, the paper band should first be moved backward through an amount corresponding to two picks (or to one card), and that before normal operation is resumed, it must be advanced through the same amount.

In accordance with the present invention, in order to rotate the dobby backwardly or forwardly independently of the loom proper, there is provided a hand lever 15 which may be manually displaced in one or the other direction (upwardly or downwardly in FIG. 1) starting from a mean position or position of rest which corresponds to the normal combined operation of the loom and of the dobby. This lever 15 is secured to a shaft 16 which also carries a cam supporting arm 17, a connecting lever 18 and a contact actuating nose 19.

The cam supporting arm 17 is integral with a flat enlarged head 17a of generally arcuate shape formed with a cam slot 17b (FIGS. 1 and 2). This slot co-acts with a roller 20 carried by one arm of a bell-crank lever 21 mounted on a stud 22. The other arm of this lever is connected by a link 23 with a toothed sector 24 carried by .a short shaft 25. The toothed sector 24 meshes with a pinion 26 rotatably supported by a stud 27, this pinion 26 having a laterally protruding finger 28 adapted to actuate a displacing wheel 29 keyed on the cylinder carrying shaft 4. The arrangement is such that at each revolution of the pinion 26, the finger 28 causes the displacing wheel 29 to rotate through an angle corresponding to one tooth.

When the hand lever 15 is at its position of rest, as illustrated in FIG. 1, the roller 20 is in the central zone of the cam groove 17b, in the portion thereof which is situated at the greatest radial distance from the axis of the shaft 16. For this position of the roller 20 the finger 28 is wholly disengaged from the displacing wheel 29 on the left-hand side of the plane which contains the axis of the wheel 29 and of the pinion 26 in FIG. 1. If now the hand lever 15 is raised, i.e., is swung clockwise (arrow AV in FIG. 1), the roller 20 remains in a portion of the cam slot 17b which is concentric to the shaft 16 and therefore the bell-crank lever 21 is not actuated. But if the lever 15 is swung downwardly (arrow AR), the roller 20 comes into a portion of smaller radius of the cam slot 17b (position of FIG. 2). The bell-crank lever 21 is thus rotated clockwise together with the toothed sector 24. The pinion 26 therefore rotates counterclockwise and its finger 28 causes clockwise rotation of the displacing wheel 29 through an angle corresponding to one tooth. The arrangement is such that this rotation of the displacing Wheel 29 causes a backward displacement of the perforated paper band 1 through an amount corresponding to one card. The finger 28 thereafter clears the wheel 29 and reaches the position illustrated in FIG. 2, on the right-hand side of the plane containing the axis of the wheel 29 and of the pinion 26.

The short shaft 25 on which the toothed sector 24 is mounted also carries :a cam 31 formed of an untoothed sector having a central hoss 31a which, when the shaft 25 is rotated, actuates a roller 32 supported by a lever 33 keyed on the above-mentioned shaft 8. The lever 33 is thus rotated counterclockwise in FIGS. 1 and 2, together with the shaft 8 and the components which it carries. The cross bar is thus momentarily raised and it in turn raises the feeler needles 12 while the positioning pawl 6 liberates the advancing Wheel 5. The arrangement is such that this occurs exactly during actuation of the displacing wheel 29 by the finger 28 is order that the cylinder may be rotated freely and that the displacement of the perforated paper pattern 1 should not be hindered by the feeler needles.

The connecting lever 18 carried by the shaft 16 actuates a link 34 the other end of which is pivotally connected with a lever 35 pivoted on a stud 36. The pivoted end of this lever is integral with a hollow triangular cam or frame 37 which co-acts with a finger 38 carried by a two-armed lever 39 pivoted at 40 (FIG. 3). The other end of this lever 39 carries a roller 41 adapted to act on a circular plate 42 supported by a sleeve 43 which is slidably keyed on a shaft 44. The latter carries a sprocket 45 connected by a chain 46 with another sprocket 47 mounted on an appropriate shaft 48 of the loom. The sleeve 43 is formed with a single lateral tooth 49 which extends through about 180 and it is submitted to the action of a spring 50 disposed between the sprocket 45 and the circular plate 42, the said spring tending to bring the tooth 49 into mesh with a complementary tooth 51 provided at the end of the hub 53 of a bevel gear 54 which meshes with a corresponding bevel gear 55 keyed on the driving shaft 56 of the dobby. The hub 53 is loose on the shaft 44, but is axially retained in position thereon. It further carries a spur gear 57.

In order to rotate the dobby independently of the loom there is provided a small auxiliary electric motor 58 associated with a speed reducing gearing 59. On the outlet shaft 60 of the latter is slidably keyed a sleeve 61 formed at its ends with pinions 62 and 63 which may he selectively brought into mesh with the spur gear 57. This sleeve 61 is axially displaced on the outlet shaft 60 by the forked end (not illustrated) of an extension 35a of the abovementioned lever 35.

When the hand lever 15 is at its position of rest illustrated in FIG. 1, the finger 38 is at the apex of the triangular cam or frame 37, the roller 41 does not act on the circular plate 42 and therefore the teeth 49 and 51 are in mesh under the action of the spring 50. When the hand lever 15 is raised or lowered, the cam 37 rotates clockwise or counterclockwise and the finger 38 is moved towards the right in FIG. 3. The roller 41 therefore moves towards the left and it disengages the teeth 49 and :51 against the reaction of the spring 50. At the same time the extension 35a of the lever 35 brings one of the pinions 62 and 63 into engagement with the spur wheel 57 which is now de-clutched from the shaft 44 and from the loom. The auxiliary motor 58 is thus connected with the dobby which is itself de-clutched from the loom.

As to the nose 19, at the position of rest of the hand lever 15, it is situated between two micro-switches which have been very diagrammatically illustrated at 64 and 65 in FIG. 3. These micro-switches control an electromagnetic reversing switch 66 inserted between the auxiliary motor 58 and the network 67. The arrangement is such that when the hand lever 15 is actuated in one or the other direction, the nose 19 actuates one or the other of the micro-switches at the end of the stroke of the lever.

The general operation is as follows:

When the hand lever 15 is at its position of rest, as illustrated in FIGS. 1 and 3, the finger 28 is disengaged from the displacing wheel 29 and it does not therefore hinder the normal advance of the paper band. The boss 31a is on the left-hand side of the roller 32 and the positioning pawl or gudgeon is therefore free to cooperate with the advancing wheel 5, the cross bar 10' raising normally the feeler needles 12 during each advance of the said wheel. The finger 38 is situated at the apex of the cam or frame 37, the roller 41 is at the position illustrated in FIG. 3 and it does not therefore prevent the spring 50 from bringing into mesh the teeth 49 and 51. The driving shaft 56 of the dobby is thus clutched with the loom for normal operation of the latter. The extension 35a of the lever 35 is at its mean position for which the pinions 62 and 63 are situated on each side of the spur gear 57 which may thus rotate freely. The nose 19 is spaced from both micro-switches 64 and 65 and therefore the reversing switch 66 is at the open position.

The dobby may thus freely operate normally in combination with the loom in the conventional manner.

When the operator has to unweave a portion of the fabric, as for instance in order to eliminate a weaving defect, he stops the loom and he actuates the hand lever in the direction AR (i.e., he lowers the lever-in FIGS. 1 and 3). The cam 17a is thus rotated counterclockwise in FIGS. 1 and 2 and its slot 171? raises the roller 20, as shown in FIG.- 2. The lever 21 rotates clockwise and through the link 23 and the toothed sector 24, it causes counterclockwise rotation of the pinion 26. The finger 28- of the latter'rotates the displacing wheel 29 through an angle corresponding to one tooth" and therefore displaces the paper band 1 backwards through one card. This rotation of the wheel 29 has been permittedby the boss 31a which has momentarily raised the positioning pawl 6 and the feeler needles 12.

- The connecting arm 18 has caused the lever 35 and the triangular cam 37 to rotate counterclockwise. This rotation of the cam has moved the finger 38 towards the right and therefore the roller 41 towards the left. The teeth 49 and 51 have been disengaged from each other against the action of the spring 50 thus de-clutching the dobby from the loom. As to the rotation of the lever 35, it has caused the right-hand pinion 63 to come into mesh with the spur wheel '57.

At the end of the downward stroke of the hand lever 15 the nose 19 actuates the micro-switch 65. The latter acts in turn on the reversing switch 67 which is brought to such a position that the auxiliary motor 58 is energized for driving the dobby backwards at a reduced speed. This energization of the motor 58 only occurs well after disengagement of the teeth 49 and 51, and after the paper band has been displaced backwards through one card.

The dobby now operates correctly with respect to the successive wefts of the fabric since the paper band has been previously displaced backwards as required. The operator may thus freely remove the weft threads from the successive sheds during the slow rotation of the dobby. He may besides stop this rotation at will by merely raising very slightly the hand lever 15 Ge, through an amount just sufficient to open the microswitch 65).

When the unweaving operation is ended, the operator releases the hand lever 15. The spring 50 then returns the triangular cam to its position of rest as illustrated in FIG. 3, together with the lever 15 itself. It is to be remarked that this return of the hand lever 15 to its position of rest could also be effected by separate spring means, as for instance by a spring urging the lever 39 to wards the left in FIG. 3. In any case the microswitch 65 opens, the auxiliary motor 58 stops, the pinion 63 disengages from the spur wheel 57 and the toothed sector 24 is returned to its initial position of FIG. 3, the finger 28 again displacing the paper band through one card, but this time in the forward direction, as required for proper operation of the dobby in combination with the loom. Here again the rotation of the displacing wheel 29 and of the paper carrying cylinder is permitted by the boss 31a which momentarily raises the feeler needles and the positioning pawl. As to the teeth 49 and 51, they are brought into mesh by the spring 50 either immediately when the hand lever 15 is released, or when the shaft 48 of the loom just begins rotating.

If for any reason the operator desires to advance the dobby independently of the loom, he merely raises the hand lever 15 in the direction AV of FIG. 1. It is quite easy to see that in this case the lever 21 remains atstandstill and that therefore the paper band is not displaced during actuation of the lever 15. The lever 35 is rotated counterclockwise and it brings the pinion 62 into mesh with the spur wheel 57 while the lever 39 is actuated by the triangular cam 37 as in the former case, so asto disengage the teeth 49 and 51. The nose ,19 actuates the micro-switch 64 and therefore the reversing switch 66 energizes the auxiliary motor 58 forforward rotation of the dobby. g t v y Here again whennormal operation of the loom is to be resumed, the operator releases the hand lever 15 which is returned to its position of rest by the spring 50, or by separate spring means if desired.

It will thus be seen that with the device according to the invention the operator of the loom may rotate the dobby backwards or forwards, as desired, without having to take care of the necessary preliminary displacement of the paper band before unweaving and. before resuming normal loom operation.

It will also be noted that instead of reversing the auxiliary motor 58, it would be possible to provide an intermediate reversing gear between the spur wheel 57 and one of the pinions 62, 63. In this case the independent rotation of the dobby could be effected by the motor normally provided for driving the loom, the said motor r being of course previously de-clutched from the loom itself.

I claim:

1. In a double lift dobby having drive means, a pattern cylinder carrying a perforated paper pattern programmed as successive pattern cards each card being programmed for two successive picks, said cylinder being intermittently driven by said drive means a distance sufiicient to position successive cards in a reading position and retained in said reading position by a positioning pawl, feeler needles operative to read said cards in said reading position, the improvement comprising a device to rotate said cylinder independently of said drive means comprising an actuating member having a position of rest and a first operative position; first means actuated by said actuating member to momentarily raise the feeler needles to an inoperative position and to disengage the positioning pawl, and thereafter to lower said feeler needles and to liberate said retaining pawl, while said actuating member is moved from its position of rest to its first operative position and when it is returned from its first operative position to its position of rest; second means actuated by said actuating member to displace said cylinder through an amount corresponding to said distance in the interval during which the feeler needles are raised and the positioning pawl is disengaged, said displacement taking place backwards with respect to the normal advancing movement of said cylinder, when said actuating member is moved from its position of rest to its first operative position, and forwards when said member is returned from its first operative position to its position of rest; clutch means interposed between said drive means and said cylinder, said clutch means being normally at the clutched position; and third means actuated by said actuating member to bring said clutch means to the declutched position when said member is moved from its position of rest to its first operative position, and to return said clutch means to their normal clutched position when said member is returned from its first operative position to its position of rest.

2. A device as claimed in claim 1, wherein said actuating member has a second operative position, said first and second means being idle while said member is moved from its position of rest to said second operative position and when it is returned from said second operative position to its position of rest.

3. In a device as claimed in claim 1, an auxiliary motor to rotate the cylinder in the backward direction independently of said drive means; fourth means actuated by said actuating member to mechanically connect said auxiliary motor with the cylinder when said actuating member is moved from its position of rest to its first oper- =ative position and fifth means actuated by said actuating member to cause rotation of said auxiliary motor when said member reaches its first operative position.

4. In a device as claimed in claim 2, an auxiliary motor to rotate said cylinder independently of said drive means; fourth means actuated by said actuating member to mechanically connect said auxiliary motor with said cylinder when said actuating member is moved from its position of rest to any of its first and second operative positions; fifth means actuated by said actuating member to cause rotation of said auxiliary motor when said member has reached any of its first and second operative positions; and sixth means actuated by said actuating member to cause said motor to rotate said cylinder in the backward direction when said actuating member reaches its first operative position and in the forward direction when it reaches its second operative position.

5. In a device as claimed in claim 4, said auxiliary motor being a reversible electric motor; said fifth means being formed of electric contacts; and said sixth means being comprised of a reversing switch actuated by said 8 electric contacts to control rotation of said reversible motor.

References Cited UNITED STATES PATENTS 3,095,015 6/1963 Cuiengnet 139-14 3,313,341 5/1967 Nollet 139-14 FOREIGN PATENTS 969,951 5/1950 France. 686,573 1/1940 Germany.

HENRY S. JAUDON, Primary Examiner. 

